TRANSIT OF VENUS EXPEDITION.

Dunstan Times, Issue 650, 2 October 1874, Page 3

TRANSIT OF VENUS EXPEDITION.

(Otago Daily Times),

Mr Bass, first assistant of the American expedition for the observation of the transit of Venus, which will take place on the afternoon of the 9th December next, las arrived in Dunedin by the San Francisco mail boat, in advance of Professor Peters, who is at the head of the expedition. Mr Bass is to select a suitable place for the ohservation, and in furtherance of this he wil proceed in a few days on a tour through the Province, accompanied by the Chief-Sur-veyor. The Council of the Otago Institute has recommended the region of Clyde, Dunstan, as being a likely locality to command an undimmed atmosphere and clear sky. The objections Mr Bass has to this district are that it would involve some difficulty and risk in the transit of the numerous delicate instruments with which the party will he equipped, and he is desirous of having a station as far south as possible. The instruments will consist of a largo refracting telescope for the observation of the transit, with astronomical clock and chronometers, all adapted for being placed in circuit with telegraphic lines. There will also be a very complete photographic apparatus for noting tbo passage of the planet across the sun’s disc. Portable buildings will be brought! from America for the purpose of housing the observers and their instruments. This is only one of eight parties equipped by the American Government—five being assigned to the Southern Hemisphere and three to the Northern. The determination of latitude and longitude will form by far the greater part of the observations, aud on this being

accurately effected by the Americans iu our own Province, and by the English expedition at Christchurch, an interchange of longitude by telegraphic signals will take place between the two parties. Our local observatory at Cavereham—the longitude of which has already been carefully established by observation of the moon and culminating sta^s—will also be placed in connection and cheeked. A farther and more elaborate interchangcfnecessarily by means of chronometer-*) of longitudes will have to take place between the French expedition at Campbell Island, the Ccrman expedition at the Auckland Islands, and the New Zealand parties. The Americans will a'so undertake a comparison of longitude by means of numerous chronometers, between New Zealand and Mclborne. The expeditions of the different nationalities, it is proposed, will, after having determined the positions of the points of their observations meet in Melboune in congress and arrange the taking of the difference of longitude between the Melbourne and Greenwich observatories by s telegraph. Immediately the telegraphic cable is laid between A. nstralia and Now Zealand the longitude of New Zealand will be verified by telegraphic signal under the direction of one of the expedition. '1 ho United States Sloop-of war, Swatara, has been specially fitted up and devoted to the distribution of the different parties in the Southern seas, and will make a circuit of the stations for that purpose. Sh* sailed from New York, under the command of Captain Ralph Chandler, on the Bth Jane, with the five Southern parties and their observers. She was to touch at Capetown first, to compare chronometers with the observatory'at that place. Next she was to proceed to Crozet Island, where, the first party, underjtho command of Captain C. W. Raymond, and Lieut. S. E. Tillman, both of the U.S. Engineers, will he left. Thence she goes to Kerguelen Lamb at which point a party'under the command of Lieut. llvan, and Lieut. Train, U.S. Navy, will take station. Thence she proceeds to Hobart |Town, Tasmania, which point will be occupied by a 'party in charge of Professor flarkness-, of the U.S. Nav.-i Observatory, and from there she goes directly to Bluff Harbour, where Professor Peters and his assistants will be landed. Chatham Island will be the last point of call, where the fifth ami last party, under Air Smith, of the U.S. Coast Survey, and his assistant, Mr Scott, will be stationed In the meantime, the vessel will make a number of trips carrying chronometers to different places, and after the' observation,, ■a r e over, she will proceed back and pick up the observers. She is expected to arrive at the Bluff on the first prox., but owing to the severe gales recently in the Southern Ocean, she may be delayed until the latter part of the month. Apart altogether from the interest which all must feel in these great practical applications of science in finding a true determination of the distance between our planet and the sun, which is really the base lino of astronomy, we have the practical and substantial advantage of having the position of'several points so ui.* raistakeably ascertained as to serve for all future time as the initial and ’closing points wherewith to test the accuracy of our Coloniftt trigonometrical surveys. Mr Bass, with the assistance furnished by Mr Thomson and Mr M‘Kerrow, of‘the Provincial Land Office, is making preliminary arrangements for the observations, and will proceed to Clyde on Saturday next.